JPH03226662A - Curable penetrant and curable developer used in solvent removing type penetration flaw detection test method - Google Patents

Abstract

PURPOSE:To develop a sharp flaw indication pattern by using a non-azeotropic mixture consisting of CFC 112 in a specific wt. ratio as a diluting solvent and a volatile org. solvent having a b.p. of below specific temp. in a specific wt. ratio. CONSTITUTION:As a curable solvent removing dye or a fluorescent penetrant, a non-azeotropic mixture consisting of 60 - 90 wt.% of CFC 112 being a diluting solvent and 10 - 40 wt.% of a volatile org. solvent having a b.p. of below 92.8 deg.C(760 mmHg) is used. When the non-azeotropic mixture is applied to the surface of a test product in penetration treatment, the volatile org. solvent having a b.p. of below 92.8 deg.C in the penetrant penetrating in a flaw part is evaporated during the period before the transfer to the next removing treatment and the concn. of the dye dissolved in the penetrant becomes high and the penetrant is cured. Since a flaw indicating pattern is developed on the uniform and smooth surface of a film by the penetrant enhanced in the concn. of the dye, a sharp indicating pattern is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a curable solvent-removable dye or fluorescent penetrant liquid and a curable quick-drying developer for use in a solvent-removable penetrant testing method.

[Conventional technology]

As is well known, penetrant testing methods are used to detect surface opening defects (hereinafter referred to as "defects") such as minute racks and minute pinholes that exist on the surfaces and welding areas of various equipment and components. 'J Is Z 2343
-1982J, and as shown in the standard, there are various penetrant testing methods that use various combinations of penetrants, cleaning agents, and developers, and the symbols of the test methods. Solvent removable stains or fluorescent penetrants and detergents classified as rvc-s and rFC-3J (
Currently, there is a penetrant test method that uses a combination of a solvent (solvent) and a quick-drying developer (hereinafter, this test method is referred to as a "solvent removable penetrant test method"). The following is shown.

A solvent-removable staining or fluorescent penetrating liquid is applied to the surface of the test item, and the penetrating liquid is left for a predetermined period of time to permeate into the defective areas.After that, the surface of the test item is cleaned using a cleaning agent. A removal process is performed to remove excess penetrating liquid remaining on the surface of the test piece, and then a developer containing fine white powder dispersed in a volatile organic solvent is applied to the surface of the test piece to form a thin layer of fine white powder. After a development process is performed to form a thin layer of paint on the surface of the coating film and to reveal a defect indicating pattern caused by the penetrant that has penetrated into the defect, the surface of the test piece is treated with a solvent-removable dye penetrant. A test method that detects the presence and location of defects by observing them under white light, or under ultraviolet light if a solvent-removable fluorescent penetrating liquid is used.

Next, a description will be given of the solvent-removable dye or fluorescent penetrant liquid and quick-drying developer that are currently widely used in the solvent-removable penetrant testing method as described above.

The solvent-removable dye penetrant contains a red oil-soluble dye (
For example, using Oil Red 58N manufactured by Nijirad Chemical, Spitazol Fast Red: manufactured by Futaba Chemical Research Institute, etc.),
1 to 5 parts by weight of the dye is combined with a plasticizer (e.g. DOP, TC
20 to 50 parts by weight of a base solvent consisting of vegetable oil (e.g., soybean oil) and a low-volatility solvent selected from xylene, alkylbenzene, trichloroethane, trifluorotrichloroethane, calpitol, butyl calpitol, etc.
It is a highly permeable liquid dissolved in 50 to 90 parts by weight of a diluting solvent consisting of a medium-boiling point organic solvent, and a typical commercially available product is Super Check UP-NU (trade name: manufactured by Mark Chick ■). . In addition, the solvent-removable fluorescent penetrating liquid is a fluorescent dye that develops a yellow-green color under an ultraviolet lamp (for example, C, T, Tsuruvent Yellow 43: manufactured by Morton Co., USA, C, 1, Fluoresocent Bright Varnish). Agent 68 (manufactured by Nippon Kayaku Co., Ltd., etc.) is used, and this is a highly penetrating liquid that is dissolved in a base solvent and a diluting solvent, similar to the case of solvent-removable dye penetrating liquid, and is a typical commercially available liquid. The product includes Super Glow D-6000 (product name: manufactured by Mark Chick).

The quick-drying developer consists of 5 to 10 parts by weight of fine white powder selected from fine magnesium carbonate powder, hydrated silicic acid fine powder, fine silicic acid anhydride powder, etc. having a particle size of 1 to 2 μm, mixed with rubber volatile oil, n-hexane, benzene, etc. , n-hebutane, methyl alcohol, ethyl alcohol, isopropyl alcohol, trichloroethane, trifluorotrichloroethane, etc. It is a dispersion liquid dispersed in a volatile low-boiling organic solvent selected from the group consisting of , n-hebutane, methyl alcohol, ethyl alcohol, isopropyl alcohol, trichloroethane, trifluorotrichloroethane, and the like. For example, the above-mentioned Super Check UP-NU is sold in combination with a quick-drying developer containing the above-mentioned various fine powders and the above-mentioned organic solvents in appropriate proportions. The above-mentioned Super Claw D-6000 is set with the Super Glow DN-60O8 (product name: Mark Chick ■).

The above-mentioned solvent-removable staining or fluorescent penetrating solution and quick-drying developer are often handled as a set, as seen in the above-mentioned examples of Super Check UP-NU and UD-NO, and are well known to those skilled in the art. In this article, we collectively refer to these three as "penetrant testing agents," so in the following, unless it is necessary to distinguish between these three, we will collectively refer to them as "penetrant testing agents." It is called.

The cleaning agent is generally a volatile organic solvent such as rubber volatile oil, n-hexane, benzine, n-hebutane, mineral turpentine, xylene, ethanol, isopropyl alcohol, trichloroethane, or trichloroethylene. However, if non-flammability is required, a mixed solvent prepared by diluting 1-Freon 113 or Freon 112 or a mixed solvent thereof with another organic solvent may be used.
It is disclosed in Japanese Patent No.-125090.

[Invention or problem to be solved]

In order to accurately perform the solvent-removable penetrant testing method as described above, it is necessary to be able to clearly observe the defect indicator pattern that appears, and for this purpose, the defect indicator pattern must be clear. is required. The sharpness of the defect-indicating pattern depends primarily on the performance of the solvent-removable stain or fluorescent penetrator and the fast-drying developer.

That is, the higher the concentration of the dye in the penetrating liquid that has penetrated into the defective area in the above-mentioned infiltration treatment, the more uniform the thin layer coating of white fine powder formed in the above-mentioned development treatment.
The smoother it is, the clearer the defect indication pattern can be obtained.

However, there is an upper limit to the proportion of dye that can be blended into solvent-removable dyeing or fluorescent penetrant liquids, and if more than 5 parts by weight is blended, it will have a negative effect on permeability, etc., so the proportion of dye blended should be high. There are limits to what you can do.

In addition, in the past, synthetic resins soluble in the organic solvents used in quick-drying developers were added to the formulation of quick-drying developers in order to form uniform and smooth thin coatings (for example, organic Attempts have been made to add polyvinyl alcohol-based or butyral-based synthetic resins when the solvent is isopropyl alcohol, but in this case, it is extremely difficult to remove the paint film from the surface of the test piece after the development process. Therefore, it is not currently implemented.

The present invention provides solvent-removable dyeing or fluorescent penetrating that can increase the concentration of dye in the penetrating liquid that has penetrated into defective areas, even though the proportion of dye blended into the product is the same as in the case of the general-purpose product mentioned above. A quick-drying developer that does not contain synthetic resins in the solution or product, and can form a uniform and smooth thin layer coating even though the removal of the coating after development is the same as with the general-purpose products mentioned above. The technical problem is to provide a clear defect indication pattern.

[Means to solve the problem]

The above technical problem is solved by providing a curable penetrant testing agent as follows.

That is, in a solvent-removable dyeing or fluorescent penetrating solution containing a dye, a base solvent, and a diluting solvent as essential components, the diluting solvent contains 11,260 to 90% by weight of Freon and a boiling point of 92.8°C (7
Volatile organic solvent less than 60 mouth Hg (same below) 10~
40% by weight of a non-azeotropic mixture of a curable solvent-removable dye or fluorescent penetrant used in a solvent-removable penetrant testing method, a white fine powder, and a dispersion solvent in a quick-drying developer whose essential components are a white fine powder and a dispersion solvent. The solvent is Freon 11260-90% by weight and a volatile organic solvent with a boiling point of less than 92.8°C 10-40%
It is a hardening type quick-drying developer used in the solvent-removable penetrant testing method, which is a non-azeotropic mixture with parts by weight.

When carrying out the solvent-removable penetrant testing method according to the above-mentioned JIS standard using the curable penetrant testing agent according to the present invention as described above, it is possible to make a clear defect indication pattern appear. It is possible to obtain highly accurate flaw detection results.

The configuration of the present invention will be explained in detail as follows.

First, Freon 112:1.1 is the most important in the present invention.
．． 2.2tetrachloro1.2difluoroethane: CCI
□F -CCI, F has a boiling point of 92.8℃ (760mm
It is a substance with a freezing point of 26°C (Hg (same below)), and it is solid at room temperature (approximately 26°C), but when mixed with other organic solvents, the freezing point lowers and it becomes a liquid even at room temperature. There is.

Next, the curable solvent-removable dyeing or fluorescent penetrating liquid according to the present invention contains 60 to 90% by weight of Freon 112 as a diluting solvent.
The formulation is similar to the general purpose solvent-removable dyeing or fluorescent penetrant solution described above, except that a non-azeotropic mixture of 10 to 40% by weight of a volatile organic solvent with a boiling point below 92.8° C. is used. Further, the curable quick-drying developer according to the present invention uses a non-azeotropic mixture of 60 to 90% by weight of Freon 112 and 10 to 40% by weight of a volatile organic solvent with a boiling point of less than 92.8°C as a dispersion solvent. Other than the point of use, the formulation is the same as that of the general-purpose quick-drying developer mentioned above.

The volatile organic solvent having a boiling point of less than 92.8° C. used in the present invention can be selected from a wide variety of volatile organic solvents. Specifically, pentane (36
, 1°C), hexane (68,7°C), 2-methylpentane (60,3°C), 2,2-dimethylbutane (49,7°C),
℃), 2.3-dimethylbutane (58.0℃), 2.4
Dimethylpentane (80.5℃), petroleum ether (30℃)
~70℃), petroleum benzene (50~90℃), cyclohexane (80,7℃), mixed pentene (32~60℃)
, methylcyclopentane (71.8℃), cyclohexene (82.97℃), dichloromethane ('39.75℃
) trichloromethane (61.2°C), tetrachloromethane (76.7°C), 1,1-dichloroethane (57.2°C)
8°C), 1,2-dichloroethane (83°48'C),
1. 1. 1 tri'y 0 x 9 tin (74,0℃)
, 1.2 dichloroethylene (60.6°C), trichlorethylene (87.19°C), 1-chloropropane (46°C)
, 6°C), 2-chloropropane (35, 7°C), 3-chloropropene (44, 96°C), 1-chlorobutane (7
8.4°C), 2-chlorobutane (68.25°C), 1
-chloro2-methylpropane (68,85°C), fluorobenzene (84,7°C), hexafluorobenzene (80,26'C), 2,2dichloro-1,1,1 trifluoroethane (27, 5°C), 1,1-dichloro-1
-Fluoroethane (32,0°C), 1.2 dibromo-
1,1,2,2 tetrafluoroethane (47.2°C),
Bromochlorotrifluoroethane (50,2°C), 1
．． 1 dichloro-2,2,3,3,3 pentafluoropropane (51.1°C), 1. '3dichloro-1,2,
2°3.3 pentafluoropropane (56,1°C),
5-fluorinated propatool (81°C), methanol (64°C)
, 5℃), ethanol (78.3℃), isopropyl alcohol (82.3℃), ethyl ether (34.6℃)
), isopropyl ether (68.27°C), 1.2 propylene oxide (34.5°C), furan (31.3°C)
), 2 methylfuran (63.7°C), tetrahydrofuran (66.0°C), 1.2 dimethoxyethane (85',
2°C), methanol (42.36°C), acetone (56°C),
, 2°C), methyl acetone (50-67°C), methyl ethyl ketone (79,57°C), methyl formate (31,8°C)
), ethyl formate (54,2°C), propyl formate (81,
3℃), methyl acetate (57.8℃), ethyl acetate (77℃), methyl acetate (57.8℃), ethyl acetate (77.
, 1°C), diethylamine (55,5°C), propylamine (48,0°C), isopropylamine (33,3°C)
), butylamine (77.0°C), 2.2.2 trifluoroethanol (73.6°C), etc. The numbers in parentheses listed for each solvent are the boiling point (76
0 mmHg), and it is desirable to select a solvent that has a boiling point difference of about 10° C. or more from that of Freon 112.

The mixing ratio of the volatile organic solvent in the present invention is important; if it is more than 40% by weight, it will take too long to evaporate during application, which is undesirable, and if it is less than 10% by weight, it will not be suitable when stored at room temperature. This is not preferable because there is a risk of it becoming a solid state.

When Freon 112 is mixed in a range of 60 to 90% by weight and the above volatile organic solvent is mixed in a range of 10 to 40% by weight, it is guaranteed that an appropriate evaporation time will be obtained during application and that a liquid state can be maintained during storage. When mixing within the above range, the mixing ratio must not be such that the mixture becomes an azeotropic mixture. The mixing ratio at which the mixture of Freon 112 and volatile organic solvent becomes an azeotrope varies widely depending on the amount of Freon 112 and the type of volatile organic solvent selected, but it can be determined by a simple experiment. can.

Incidentally, an appropriate amount of a rust preventive agent such as nitromethane or ethylenediamine may be added to the formulation of the curable penetrant flaw detection agent according to the present invention, if necessary.

The curable penetrant flaw detection agent according to the present invention is easy to prepare, and can be prepared by weighing, mixing, and stirring the required materials in the required proportions.

It is convenient to handle the prepared curable penetrant tester according to the present invention if it is sealed in an aerosol can with a propellant at a filling pressure of about 3 to 5 kg/crt according to a conventional method and used as an aerosol type.

Next, the method of using the curable penetrant testing agent according to the present invention is no different from that of the general-purpose penetrant testing agent mentioned above, and the mode of use thereof is completely the same as the typical mode of the solvent removable penetrant testing method described above. It's the same.

[Effect]

When the solvent-removable penetrant testing method is carried out at room temperature according to the representative embodiment using the hardening type penetrant testing agent according to the present invention, a clear defect indicating pattern will appear due to the following actions.

That is, in the curable solvent-removable dyeing or fluorescent penetrating liquid according to the present invention, the diluting solvent or Freon 11 with a boiling point of 92.8°C is used.
2 and a volatile organic solvent with a boiling point of less than 92.8°C are mixed at a predetermined mixing ratio to form a non-azeotropic mixture. During the process, the volatile organic solvent with a boiling point of less than 92.8°C in the infiltrating liquid that has penetrated into the defect area evaporates, and the concentration of the dye dissolved in the infiltrating liquid increases. As it goes, the penetrating liquid hardens (solidifies).

Further, in the curable quick-drying developer according to the present invention, the dispersion solvent is Freon 112 with a boiling point of 92.8°C and CFC 112 with a boiling point of 92.8°C.
Since it is a non-azeotropic mixture that is mixed with a volatile organic solvent at a predetermined mixing ratio of less than Alternatively, the hardened penetrant is dissolved and a thin layer formed by the fine white powder in the developer formulation absorbs the penetrant, but during this time, a volatile material with a boiling point of less than 92.8°C is removed from the dispersion solvent. As the organic solvent evaporates, the remaining Freon 112 hardens (solidifies).
A uniform and smooth coating film containing white fine powder particles as a core is formed.

Therefore, in the present invention, the defect indicating pattern appears on the even and smooth surface of the coating film due to the penetrating liquid having a high dye concentration, so that the defect indicating pattern becomes clear.

Furthermore, in the present invention, since the penetrating liquid and the thin coating film are cured, when observing the defect indicating pattern after the development process, even if there is a long time interval between the end of the development process and the time of observation. , the defect indication pattern does not bleed excessively,
This allows detection performance to be maintained constant.

〔Example〕

Next, the present invention will be explained with reference to formulation examples, solvent removability penetrant test evaluation results, and test examples.

1. Curing solvent removable dyeing or fluorescent penetrant formulation: A. Freon 11273% by weight and n-hexane 10% by weight
, 5% by weight of TOP (manufactured by Daihe Kagaku), 10% by weight of TCP (manufactured by Daihe Kagaku), and Spitazol Fast Red FW (
A penetrating solution was prepared by sufficiently mixing 2% by weight of 2% by weight (manufactured by Futaba Kagaku Kenkyushin).

The freezing point of this permeate was 7°C.

B, 11265% by weight of Freon and 20% by weight of methylene chloride
A penetrating solution was prepared by thoroughly mixing 10% by weight of DOP (manufactured by Daihe Kagaku) and 5% by weight of Sudan Red (manufactured by BASF). The freezing point of this permeate was 13°C.

C, Freon 112 73.5% by weight and n-hebutane 10
Weight%, DOP (same as above) 5% by weight and TCP (same as above) 1
0% by weight and Oil Red 58N (manufactured by Shirad Chemical Co., Ltd.) 1.
A penetrating solution was prepared by thoroughly mixing 5% by weight. Note that the freezing point of this penetrating liquid was 9°C.

D, 11276% by weight of Freon and 10% by weight of n-hebutane
, TCP (same as above) 10% by weight and Sudan Red 462
(BASF) 4% by weight was thoroughly mixed to prepare a penetrating solution. Note that the freezing point of this penetrating liquid was 13°C.

E, 78.5% by weight of Freon 112, 10% by weight of 1.1.1 trichlorothane, 10% by weight of TCP (same as above), 1% by weight of Solvent Yellow 43 (manufactured by Morton), and White Fluor B (manufactured by Sumima Chemical Co., Ltd.). ) and 0.5% by weight to prepare a penetrant solution. Note that the freezing point of this penetrating liquid was 13°C.

2. Curing type quick-drying developer formulation: F, Freon 11282% by weight and n-hexane 10% by weight
Magnesium carbonate AM-50 (manufactured by Asahi Glass) in a mixture with
A developer was prepared by dispersing 6.5% by weight and 2% by weight of Erosil #200 (manufactured by Nippon Aeroseal).

G. A mixture of 270% by weight of Freon 11, 22% by weight of isopropyl alcohol, and 1% by weight of Olben (manufactured by Shiraishi Kogyo), 2% by weight of Carplex #1120 (manufactured by Shionogi & Co., Ltd.) and 4% by weight of TT magnesium carbonate (manufactured by Tokuyama Soda). A developer was prepared by dispersing %.

H, Freon 11269% by weight and n-hebutane 10% by weight
and 12% by weight of methylene chloride and 2% by weight of olben (same as above).
A developer was prepared by dispersing 6% by weight of calcium carbonate (manufactured by Shiraishi Kogyo) in a mixture of

1.70211262% by weight and 30% by weight of methylene chloride
A developer was prepared by dispersing Erosil #200 (same as above) and 6% by weight of Magnesium Carbonate Silver Star (manufactured by Shinshin Kagaku).

J. A developer was prepared by dispersing 6% by weight of Magnesium Carbonate Silver Star (same as above) and Erosil #200 (same as above) in a mixture of 282% by weight of Freon 11 and 10% by weight of ethyl alcohol.

3. Performance evaluation results (1) Based on the U.S. military standard MIL-1-25135D, a performance comparison was made between the curable solvent-removable dye penetrant of formulation 1-A-D and the aforementioned Super Check UP-NU at room temperature. went.

That is, a quench-cracked 2024 aluminum alloy test piece (a rectangular plate measuring 76 mm x 51 cm with a thickness of 8 ann was created based on the same standard, and was divided into two by providing a 2-x2 groove in the center of the surface, and one side was the A side, The other side is the B side), and on the A side, apply the hardening type solvent removable dye penetrating liquid of Formulation 1-A using a brush, and on the B side, use a brush to apply Super Check UP-NU. After applying it and leaving it for 10 minutes, wipe both sides with dry and clean paper towels to remove excess penetrating liquid. Both sides were wiped with a paper towel impregnated with Mark Chick ■) to remove excess penetrant.

Next, the aforementioned Super Check UD-NU (aerosol type) was sprayed uniformly on both sides at a distance of approximately 30 an from the test surface, and after being left for 5 minutes, the defect indication patterns on both sides were visually compared. was slightly better.

The same performance comparison as above was made for Formulation 1-B-D, but in all cases, the clarity of the defect-indicating bleeding pattern was slightly better on side A (the side using the product of the present invention).

For the curable solvent-removable fluorescent penetrant liquid of Formulation 1-E,
The above-mentioned Super Glow 0D-6000 was used as a comparative product, and Super Glow R-11 (trade name: manufactured by Mark Chick ■) was used as a cleaning agent in the same manner as above (visual comparison was performed under ultraviolet lamp irradiation). ), and Formulation 1-E was superior in the clarity of the defect-indicating bleeding pattern.

(2), ・Prescription 2-F-J according to the same standards as (1)
hardening type quick-drying developer and the aforementioned Super Check UD-N
Performance comparison with U (aerosol type) was conducted at room temperature.

That is, Super Check UP-NU was applied to both sides of A and B of the same test piece as in (1), and after leaving it for 10 minutes, both sides were wiped with a dry and clean paper towel to wipe off the excess penetrating liquid, and then, Both sides were wiped with a paper towel impregnated with the aforementioned Super Check UR-NU to remove excess penetrant. Next, the B side was masked to prevent the developer from adhering, and the hardening type quick-drying developer of formulation 2-F was sealed in an aerosol can with a propellant at a filling pressure of about 4 kg/d according to a conventional method to form an aerosol type. Spray evenly on side A from a distance of approximately 30 mm from the test surface, immediately mask side A to prevent developer from adhering, remove the mask on side B, and test Super Check UD-NU (aerosol type). Spray evenly on side B at a distance of about 30 cm from side, then remove the mask on side A and leave it for 5 minutes.
When the defect indicating patterns on both sides were visually compared, the clarity was slightly better than that of side A.

For Formulation 2-G-J, performance comparisons were made in the same manner as above, and in all cases, side A (the side using the product of the present invention) was slightly superior in clarity of the defect-indicating bleeding pattern.

In addition, the same performance comparison as above was carried out for formulation 2-F with 1 wt% of ethylenecyamine added and formulations G to J with each of 1 wt% of nitromethane added. No particular change was observed due to the addition of the antifungal agent.

4. Solvent-removable dye penetrant test example At room temperature, a hardening type solvent-removable dye penetrant with formulation IA was applied with a propellant to a type A comparison test piece for sensitivity testing according to the J I 5-Z-2343-1982 standard. After filling an aerosol can with a filling pressure of about 4 kg/car according to a conventional method and spraying it evenly as an aerosol type from a distance of about 15 ann from the test surface and leaving it for 5 minutes for penetration treatment,
The test piece was wiped dry with a dry rag, and then the excess penetrant was wiped off with a rag impregnated with the aforementioned Super Check UR-NU. A quick-drying developer was sealed in an aerosol can with a propellant at a filling pressure of about 5 kg/cd according to a conventional method, and sprayed uniformly at a distance of about 30 ann from the test surface to a thickness of about 30 μm.
After a thin coating film was formed and developed for 7 minutes, the test piece was visually observed, and a clear red defect indicator pattern was clearly observed on a white background.

5. Solvent-removable fluorescent penetrant testing test example At room temperature, a curable solvent-removable fluorescent penetrant liquid of Formulation 1-E was applied to a type A comparison test piece for sensitivity testing according to JI 5-Z-23431982 standard together with a propellant. Fill an aerosol can with a filling pressure of about 4 kg/cd according to the usual method, spray it uniformly at a distance of about 15 ann from the test surface, and leave it for 5 minutes for penetration treatment, and then dry the test piece. The test piece was then wiped clean with a rag soaked in Super Glow R-n, and then the excess penetrating liquid was wiped off with a rag impregnated with the aforementioned Super Glow R-n. Approximately 4k with propellant
Fill an aerosol can with a filling pressure of g/ai according to the usual method to make an aerosol type.
After separating and spraying uniformly to form a thin coating film with a thickness of about 30 μm and developing it by leaving it for 7 minutes, the test piece was visually observed under UV lamp irradiation in a dark place. A bright yellow-green fluorescent defect indicator pattern was clearly observed.

〔Effect of the invention〕

When the curable penetrant flaw detection agent according to the present invention is used, a defect indicating pattern caused by a penetrating liquid with a high dye concentration appears on the uniform and smooth surface of the coating film, so the indicating pattern becomes clear and The solvent removable penetrant testing method can be performed with high accuracy without excessive blurring of the defect indicating pattern.

Claims (2)

[Claims] (1) In a solvent-removable dyeing or fluorescent penetrant solution that uses a dye, a base solvent, and a diluent solvent as essential components and is used in a solvent-removable penetrant test method, the diluent solvent is Freon 1126.
A curable solvent used in a solvent-removable penetrant testing method, characterized in that it is a non-azeotropic mixture of 0 to 90% by weight and 10 to 40% by weight of a volatile organic solvent with a boiling point of less than 92.8°C (760 mmHg). Removable stain or fluorescent penetrant. (2) In a quick-drying developer whose essential components are a white fine powder and a dispersion solvent used in the solvent-removable penetrant test method,
The dispersion solvent contains 11,260 to 90% by weight of Freon and a boiling point of 9.
Volatile organic solvents below 2.8°C (760mmHg) 10
A hardening type quick-drying developer used in a solvent removable penetrant testing method, characterized in that it is a non-azeotropic mixture with ~40 parts by weight.